John McCain Could Energize
Or Shock the GOP Convention

WASHINGTON -- John McCain's "Straight Talk Express" rolls into Philadelphia Saturday, with his 89-year-old mother, Roberta, in tow. "I'll sit on your lap," she tells a reporter. "It will be crowded."

It will, indeed. Even now, with the Republican ticket in place without him, the Arizona senator generates enough electricity that he stirs anxious hearts in George W. Bush's headquarters in Austin, Texas. Poll after poll shows Mr. McCain enjoying more-positive ratings in swing congressional...